Smoke-consumer for furnaces, &amp;c.



No. sssom Patented nec. l2, i899. J. A. cnAwFoRD.

sMoKE consumen Fox FuRNAcEs, ae'.

(Appuczian mea July 12, 1899.) Y (H0 Model.) 3 Sheets-Sheet l.

162 www@ No. 638,800. Patented Dec. l2, |899.

J. A. CRAWFORD.

SMOKE CONSUMER FOB FURNACES, 8m.

(Application led July 12, 1899.)

l (No Model.) 3 Sheets-Sheet 2. y. p Z? f .ZZ/jfl zx wmsss l 27 wnvw'. yWww 2%. a. WMQ M l (9 www n r ,ax/t' l Patented Dec. I2, |899.

3 Sheets-Sheet 3.

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J. A. CRAWFORD. SMOKE CONSUMER FDR FURNAGES, c. (Application Sled July1B, 1899.)

(No Model.)

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JOHN A. GRAVFORD, OF ALLEGIIENY, PENNSYLVANIA.

SMOKE-CONSUMER PGR FURNACES, &G.

SPECIFICATION forming part of Ilhetters Patent No. 638,800, datedDecember 12, 1899. Application led July 12,1899. Serial-No. 723,598. (Nomodel.)

To @ZZ whom, z'f may con/cern.'

Be it known that I, JGHN A. CRAWFORD, a citizen of the United States ofAmerica, residing at Allegheny, in the county of Allegheny and State ofPennsylvania, have invented certain new and useful Improvements inSmoke- Consumers for Fuinaces,&c.; and I do hereby declarethe followingto be a full, clear, and exact description thereof, reference being hadto the accompanying drawings, which form a part of this specication.

My invention relates to smokeconsu1ners for steam-boiler and otherfurnaces, and it is an improvement on Letters Patent granted to mebearing date of May21, 1895, No. 539,768, and No. 586,477, dated July13, 1897; and the object of the invention is to conduct partiallyheatedair from the ash-pit and more intensely heated air from a casing in thebridge-wall, said casing taking partially-heated air from the aslrpitand form counter-drafts to the smoke-stack, whereby by a propermanipulation of the steam jets, valves, and dampers regulating andcontrolling the currents of air to the lire-chamber the smoke will beentirely eliminated and a better and more intense combustion produced.

Another object of my invention is to provide a means for preventing theclogging of the pipes or iiues from ashes and small particles of fueldrawn from the iire-chamber,and also to provide a steam-jet of peculiarconstruction for use upon this particular construction ofsmoke-consuming device that will not easily clog and when so cloggedwill easily be cleaned.

The invention linallyeonsists in the certain details of construction andcombination of parts, as will be fully described hereinafter.

In the accompanying` drawings, Figure 1 is a sectional front elevationof my improved smoke-consuming device, which is constructed and arrangedin accordance with my invention, the said section being taken on theline y 'y of Fig. 3. Fig. 2 is a front elevation of the same, partly insection. Fig. 3 is'a longitudinal section vertically through thefurnace, showing the arrangement of one of the gas and air pipes in thefront wall, the slot 8 in the side wall, and the arrangement of thesteanrfeeding pipe to the jet-pipes. Fig. a is a sectional plan viewtaken on the line .fr of Fig.1. Fig.

5 is an enlarged sectional elevation of one of the pipes arranged in theside wall of the furnace for conducting the air and gas to the point ofcombustion. Fig. 6 is a similar view of the pipes used in the front wallof the furnace. Fig. Tis a detail of one of the short pipes used when anobstruction is met. Fig. 8 is an enlarged detail section through thebridge-wall, showing'valve for controlling hot-air iues. Fig. 9 is adetail of the valve on bottom of pipe or air-fines. Fig. 10 is anenlarged sectional view of one of the steam-jets. Fig. 11 is a similarView showing the manner in which the jet is arranged within the tube.

To construct and arrange a smoke-consumer in connection with a boiler.or other'furnace in accorda-nce with my invention, the said furnace,consisting of the boiler 1, the sidewalls 2', the bridge-wall 3, thelire-chamber beneath the boiler, the ash-pit 6, the usual metal casing5G,and grate-bars 6', and other well-known features not necessary todescribe, I arrange at each side of the furnace or fire-chamber and uponthe same plane as the grate-bars 6 two air-boxes, each of which consistsof a box 7 of a length equal to that of the fire-chamber and having anopening 8 leading to the said chamber, the opening being in the form ofa slot and extending the entire length of the grate-bars, and the saidboxes provided with openings through the top, bottom, and ends forconnections with hot and cold air pipes, hereinafter described.

Formed in the front wall of the lire-chamber is a flue 20, communicatingwith the front ends ofthe airboXes 7, and the said fiue having severalhot-air pipes 19 leading therefrom, each of which is connected with aninclined connection 18, fitted with a steamjet 33, and connected inmultiple to abranch pipe S4, leading from a main supply-pipe 29,connected to the steam-dome 4 of the boiler 1. A valve 35 is placed inthe pipe 29 to regulate the flow of steam to the jet-pipes.

The pipes 10 are formed with an intake branch 19", opening from thelire-chamber above the gratebars, through which the gases from thehre-chamber enter, and at the lower end of the pipes 19 is formed anair-intake branch 20', leading from the ash-pit. Each of thesesteam-jets is controlled by a valve and used to siphon a current ofheated air from the box 7 and discharge the same at a point within thefire-chamber above the line of fuel. This air upon its passage gathersmore or less heat from the walls in which the pipes 19 are embedded andfrom the flue 2O and box 7, as well as from the ash-pit beneath, andwhen discharged into the furnace will produce better combustion of thegases arising from the fuel in the form of smoke or Waste products ofcombustion at this particular part of the firechamber.

Connected to the bottoms of the air-boxes 7 area suitable number ofshort pipes orfiues 11, leading to and in communication with the ash-pit6, and are used for the purpose of drawing the partially-heated air fromthe said pit into the ai r-boXes 7. Each of these pipes 11 is providedat its base with a valve or damper l2 (see Figs. 5 and 9) to regulatethe currents of air entering the same, and the said dampers connected bybars 14 at each side of the ash-pit, by means of which each set ofdampers may be opened or closed by the operator at the front of thefurnace. Each of these short pipes 11 is fitted with a steam-jet 24,consisting of (see Figs. 8 to 10 and 11) a short piece 0f tubing 24,having attached in its forward end by means of a screw-thread a taperingplug 37, provided with a small central channel 3S, the jet 39 of whichis within the tube 24, leaving an annular space about the said jet togather the particles of dust or dirt. These jets 24 used with the shortpipes 11 are provided with valves which are connected in multiple tobars 15, projecting through the front of the furnace, and are used toadmit or shut off steam to the jets and the said jets used to siphonheated air from the ash-pit anddischarge the same intovertically-arranged hot-air pipes 9, connected to the top of theair-boxes 7, the

jet-pipes being coupled at their bases by thepipe 13, which is acontinuation of the pipe 2J. These hot-air pipes 9 (see Fig. 5) arearranged and connected to the air-boxes 7 at either side of the furnaceand lead to and discharge at a point above the line of fuel, at whichplace the currents of heated air and gases are deflected downward bybent exits lO, where the said su perheated air and gases mingle with thesmoke and gases arising from the fire will cause instantaneouscombustion, consuming the smoke and further aiding the combustion of thefuel. In the side walls is formed an air passage or channel 16, adjacentto the upper ends of the hot-air pipes and opening therein through aslot or opening, as shown, the channel 16 being a continuation of thechannel 20 in the front of the furnace and serves the same purpose.

Arranged within the bridge-wall 3 and in communication with the rear endof one of the air-boxes 7' and with the ash-pit 6, by means of flues 22and 26, is a pipe 2l, fitted with a damper 23 and steam-jet 24,regulated by a valve 28 and connected with the steampipe 34 by a branch27. This pipe 21 siphons air from the ash-pit 6 and delivers the same ata high temperature to the air-box 7 and is there withdrawn anddischarged into the furnace by means of the hot-air pipes 9, abovedescribed.

The hot-air pipes 9,by means of theirsteamjets 24, will draw the smokeand products of combustion through the slots Sinto the boxes 7 andintheir passage upward be superheated when discharged into thefire-chamber and instantly consumed.

To control and regulate the various currents of heated air and gasesdischarged into the fire-chamber by the pipes and flues, previouslydescribed, and to retard the draft to prevent too rapid combustion ofthe fuel and also to burn any unconsu med smoke and gases that may haveescaped to the draft-stack 5 by improper manipulation of the variousdampers and valves of the apparatus, two sets of hot and cold airpipes29 and 30 are arranged at each side of the furnace, the one of each setleading from the ash-pit 6 and the other from the air-box 7 and bothsets entering the draft-stack 5 at a point above the boiler l. Each ofthe cold-air pipes 29 terminates in the draft-stack 5 at a point somedistance below the hot-air pipes 30,and each of the said pipes fittedwith a damper 3l to open and close the passages of the same.

By means of the pipe 29, leading from the ash-pit 6, a counter-draft iscreated which tends to draw the smoke downward through the grate-bars,thereby retarding the fire by forming a draft to the stack 5. The pipes30, leading from the air-boxes 7, are used to supd ply heated air andgases to ignite and consume any smoke found within the draft stack 5,which is often the case when the currents `of superheated air suppliedto the rechamber are not properly regulated or when a surplus of greenfuel is thrown upon the fire.-

Good results may be obtained from the cold-air pipe 29 when theinlet-openings are located outside of the furnace, as a direct draft maybe formed to retard the fire, as is obvious.

By using .the various currents of super-A heated air and gases, eitherseparately or the one current with the other, until the proper degree oftemperature is obtained perfect combustion of the smoke and fuel issecured.

Each of the hot and cold air pipes 29 or 30 may be fitted with asteam-jet, if so desired, and other slight modifications and changesmade without departing from the spirit of theinvention.

Having thus described my invention, what l claim, and desire to secureby Letters Patent, is-` 1. In combination with a steam-boiler or otherfurnace, the hot-air boxes 7, arranged within the side walls of thefurnace and at each side thereof, a slot or opening formed in the saidboxes communicating with the interior of the lire-chamber upon the sameplane as the grate-bars, suitable hot-air flues lead ICQ ing from thesaid boxes and discharging into the fire-chamber above the line of fuel,steamj ets entering the said hot-air pipes and terminating above theair-boxes, and valves for regulating the amount of air entering thehotair pipes, as described.

2. In combination with a steam-boiler or other furnace, the hot-airboxes provided with slots extending along the entire length of thefire-chamber and upon the same plane as the gratebars, in combinationwith a hotair pipe 30 leading from the said box and terminating Withinthe draft-stack above the boiler, as and for the purpose described.

3. In combination with a steam-boiler or other furnace, the hotair box 7provided with a slot extending along theentire length of thenre-chamber, and upon the same plane as the grate-bars, a series ofhot-air pipes provided with dam pers, and leading from the ash-pit, aseries of siphon pipes or iiues arranged in the front Wall of thefurnace, communicating with the ash-pit and with the ends of theair-boxes, whereby superheated air and gases are discharged into thefurnace above the line of the fuel, as and for the purpose described.

Li. In combination with a smoke-consuming device such as described, thehot and cold air pipes leading to the draft-stack, the cold air havingan entrance to the ash-pit, and the hot-air pipe communicating with theinterior of the fire-chamber, suitable steam-jets arranged in the saidpipes for creating a forced draft, whereby the smoke and products ofcombustion may be drawn downward through the fire, substantially asdescribed.

In testimony whereof I have hereunto af-V fixed my signature in thepresence of two sub= scribing Witnesses.

JOHN A. CRAWFGRD.

IVitnessest H. G. MEHRING, M. E, HARRISON.

